Chbistopher j



C. J. LAKE. AIRPLANE.

APPLICATION FI I.ED AUG.14. 19I7.

1 ,307, 1 33. Patented June 17, 1919.

W/ .6. my. 5.

ATTORNEY UNITED STATES PATENT OFFICE.

cnmszrorimn J. LAKE, or BRIDGEPORT. CONNECTICUT.

- Application filed August 14,

To all whom it may concern:

Be it known that I, CHRISTOPHER J. LAKE, a citizen of the United States, andresident of Bridgeport, in the county of Fairfield and State of Connecticut, have invented certain new and useful Improvements in Airplanes, of which the following is a-specification.

This invention relates toairplanes, and" my improvements are directed to means of lateral and directional control,- through the medium of auxiliary aerofoils, which also serve to supplementthe supporting area afiorded by the main supporting wing surace.

In brief my invention consists of a movable aerofoil disposed above or below the longitudinal axis of an airplane, or movable aerofoils disposed both above and below said longitudinal axis, fol-lateral control; and of a movable aerofoil disposed fore or aft of the vertical axis of the .airplane, or movable aerofoils disposed both fore and aft of said vertical axis, fof directional control.

These control aerofoils correspond, in their general construction and arrangement, only differing in their respective functions, which they are enabled to performon account of the particular locations they occupy upon the airplane.

The said control aerofoils,in their common character, each resemble the main supporting unit inan airplane, buton a smaller scale, and are pivotally supported in manner to present a normal or moderate angle of incidence to the' supporting pressure in theline of flight. The angle ofincidence for the aerofoil, thus established and set, is however variable relatively to the longitudinal axis of the airplane, underla lateral pivotal movement of said .aerofoil, [to progressively enhance its control potential according to the increase of angularity imported therein.

This variability in angularity of incidence in the turning movement of the aerofoil may be acquired by providingfore and aft bearings in differently distanced parallel planes relatively to. the longitudinal axis of the airplane, a rearward pivot for the aerofoil engagingits bearing at a greater distance from said axis-than the forward pivot, but said forwardpivot being borne .by a brack t which upp rts the forward portion of the r f il ,more, distant from said axis than Specification of'letters Patent.

. tion..

supports 9, 10, are engaged by pivots 11, 12,

Patented June 17, 1919.

1917. Serial 110.186.149.

the horizontal plane of its rearward por- Other features and advantages of my said invention will hereinafter appear.

In the drawing Figure 1 is a side elevation of an airplane having my improved control aerofoils.

Fig. 2 is a front view thereof.

Fig. 3 is a perspective elevation of one of the directional control aerofoils in its normal or central position as an auxiliary supporting surface.

Fig. 4 is a side elevation thereof, and Fig. 5 is a plan view. Fig. 6 is a perspective elevation of the same aerofoil as swung in one direction to the limit of its angular disposition for directional control.

Fig. 7 is a side view thereof, and

Fig. 8 is a plan view.

In the example of my invention illustrated herewith I haveshown an airplane having the main supporting unit 1 with fuselage or body portion 2.

The representation is more or less diagrammatic and is not inclusive of motor, propeller or other features, non-essential to a comprehension of my improvement.

Directional control aerofoils are shown at 3 and l respectively, and lateral control aerofoils at 5 and 6. Bearings 7, 8, carried by respectively, which depend from brackets 13, 14, that, respectively connect with the forward portions of aerofoils 3 and 4. The

rear portions of said aerofoils have pivots 15,

16, respectively, provided closely adjacent thereto, and engaging in bearings 17 18, respectively, lying in a horizontal plane above that of the forward bearings 7, 8, and carried, respectively, by standards 19, 20.

By this construction, while the rear portion" of the aerofoil swings substantially about its center, the forward portion thereof rocks in an are having a radius equal to the distance separating said forward portion from its bearing, which latter is in a lower plane than the bearing for said rear portion.

Obviously, the pivotal arrangement here indicated is only by way of example, since the same set of the aerofoils may be attained by other pivotal means.

The aerofoils 3, 4, when in their normal position shown inFigs. land 2, have a set angle of incidence, which may be, for example, 4, or such other desirable angle as, in accord with the general design of the airplane, will add lift thereto, and thus supplement the lifting surface afforded by the main supporting unit. But when the aerofoils 3, 4, are to be used as controls or rudders for horizontal direction, then they are swung oppositely upon their fulcra to thereby also impart a turning movement of the airplane about its vertical axis.

Fig. 6 shows the aerofoil 4 as swung over to a maximum degree of movement upon its pivots, to which point the angle of incidence of said aerofoil, relatively to the longitudinal axis of the airplane, has advanced progressively.

In this movement the vertical force which was sustaining the aerofoil, is resolved into vertical and lateral components, and by means of the latter components the desired directional effort, supplementary to the sustaining effort, is obtained within the range of available movement. Thus, as an aerofoil is rocked toward either side of the central position, its angle of incidence increases with relation thereto, whereby the rotative influence of said aerofoil is augmented.

The bearings 7 8, for the aerofoils 3, 4,

may carry pulleys 21, 22, respectively, around which cables 23, 24, may be passed, for manipulation of said aerofoil. Also, the aerofoils may be so interconnected in a manner known in this art, that they will be caused to operate oppositely, in unison; or in the same direction, to compensate for drift.

The lateral control aerofoils 5, 6, corresponding in general character with the aerofoils 3, 4, are arranged in the vertical axis of the airplane, respectively above and below the main supporting unit 1. These aerofoils have rear pivotal supports 26. and forward pivotal supports 27, which enable them to operate, under similar means of manipulation, in the same manner as the aerofoils 3, 4.

The aerofoils 5, 6, like the aerofoils 3, 4, when in normal position, function as auxiliary supporting surfaces; but when rotated oppositely, as by suitable control means, they also function to rotate the airplane about its longitudinal axis, and thereby provide lateral control means of highly efiicient character for said airplane.

Variations may be resorted to within the spirit and scope of my invention, and parts thereof used without others I claim:

1. In an airplane, an auxiliarv aerofoil presenting, for support. a normal angle of incidence in the line of flight, said aerofoil turnable about a fixed lengthwise axis, in the central vertical plane of, and so inclined forwardly downward to the longitudinal axis of the airplane, that said aerofoil, for control, presents varying angles of incidence to said longitudinal axis.

2. In an airplane, an auxiliary aerofoil. presenting, for support, a normal angle of incidence in the line of flight, and said aerofoil having fixed lengthwise pivotal means whose axis is inclined oppositely to said normal angle of incidence, whereby, when rocked for combined support and control, "said aerofoil progressively increases its angle of incidence through the arc of its movement in either, direction.

3. The combination, in an airplane having a main supporting unit, of pivotal aerofoils disposed respectively fore and aft of said unit, said aerofoils presenting minimum angles of incidence to the longitudinal axis of the airplane, when positioned as supporting members, and said aerofoils being turnable oppositely through limited arcs, each with progressivel increasing angles of incidence, foicom ined support and directional control of said airplane.

4. The combination, in an airplane having a main supporting unit, of pivotal aerofoils disposed respectively above and below said unit, said aerofoils presenting minimum angles of incidence to the longitudinal axis of the airplane, when positioned as supporting members, and said aerofoils being turnable oppositely, through limited arcs, each with progressively increasing anglcs of incidence, for combined support and lateral control of the airplane.

5. In an airplane, an auxiliary pivotal aerofoil with forward and rear bearings whose axis intersects the longitudinal axis of said airplane, said aerofoil being supported extendingly from its forward bearing, to accord it a normal angle of incidence when functioning only as a supporting member, and whereby, when turned in either direction for control purposes, its angle of incidence relatively to said longitudinal axis, increases progressively.

6. The combination, in an airplane, of an auxiliary aerofoil, for support and control, and pivotal means therefor whose axis is fixed and lies rearwardly upward at an angle of less than 45 degrees with relation to the central longitudinal line of said airplane.

7. The combination, in an airplane having a main supportingunit, of pivotal aerofoils disposed respectively fore and aft of said unit, said aerofoils presenting minimum angles of incidencetothe longitudinal axis of the airplane, when positioned as supporting members, and said aerofoils being turnable through limited arcs, each with progressively increasing angles of incidence, for combined support and directional control of said airplane.

8. The combination, in an airplane having a main supporting unit, of pivotal aerofoils disposed respectively above and below said unit, said aerofoils presenting minimum angles of incidence to the longitudinal axis of the airplane, when positioned as support-' ing members, and said aerofoils being turnable through limited arcs, each with progressively increasing angles of incidence, for combined support and. lateral control of the airplane.

Signed at the borough of Manhattan in 15 the city, county and State of New York this 13th day of August A. D. 1917.

CHRISTOPHER J. LAKE.

Witnesses:

MONTAGUE PALMER, F. W. BARKER. 

